The present invention relates to archery arrow nocks with a light-emitting feature, commonly referred to as illuminated or lighted nocks.
Tracing the flight of an arrow in low light conditions, such as those found at dawn and dusk, is difficult and often impossible. There are a variety of approaches attempting to address this issue, many of which use arrows including illuminated nocks that can be seen in low light. Two examples of conventional illuminated nock technology are illustrated in U.S. Pat. No. 6,390,642, to Simonton, and U.S. Pat. No. 7,316,625 to Takahashi.
Simonton discloses an illuminated arrow nock that is activated by a magnetic field. The arrow nock includes a normally open magnetic reed switch connected to a battery, circuitry, a light and a riser magnet that must be mounted to a riser of a bow from which the arrow is shot. When the arrow is shot, the normally open magnetic reed switch passes through the magnetic field of the riser magnet, which closes the magnetic reed switch, which completes the circuit between the battery and the light to illuminate the light. The circuitry also includes a capacitor which discharges to eventually interrupt the circuit between the battery and the light after a predetermined amount of time. The circuitry can also include a processor that pulses or blinks the light after being actuated by the reed switch. Although Simonton provides an illuminated nock, it provides added complexity and opportunity for system failure by requiring the nock to pass through the magnetic field of the riser magnet. Further, due to the light automatically de-powering after a programmed amount of time, archers sometimes must search for the arrow under pressure, knowing that the light may soon de-power.
Takahashi discloses an illuminated nock that includes an electrical circuit that has a normally open acceleration switch, a capacitor circuit, a battery and an LED. The acceleration switch includes two thin metal plates, which are separated by a distance. When the arrow is shot from a bow, the thin plates bend and contact one another, thereby completing the circuit between the battery and the LED to light the LED and charge the capacitor circuit. After the arrow reaches constant speed, the metal plates separate so power is no longer provided from the battery to the LED. The capacitor, however, continues to provide its charge to the LED. After a predetermined amount time, however, the charge of the capacitor is depleted, and the LED de-powered. Like Simonton, due to the light automatically de-powering after a predetermined amount of time, archers sometimes must search for the arrow under pressure, knowing that the light may soon de-power.
Although the nocks of the above references provide desired illumination, they suffer the noted shortcomings. In addition, while these references include holders for the related batteries, these holders sometimes may not adequately retain the battery, and may also render battery replacement very difficult, which is unappealing to consumers.